I have an SSIS MULTICAST object that splits my flow into 2 paths.
1st path: i need to update a row;
2nd path: I need to insert a row.
Basically, I am implementing SCD TYPE2 data in SSIS without using SCD wizard. So after I have identified the record that has been changed in the source data, i need the '1st path' to expire that record while the '2nd path' to insert the changed record in the destination table.
I need a way to make 2nd path wait until the 1st path has finished. (otherwise, the 1st path will also update the newly inserted row by the 2nd path).
Any help is appreciated.
Multicast is parallel operation, so you cannot make one path to wait for another.
So, What you need to do is, temporarily store the data in memory and process them later to insert into the destination (for SCD Type 2).
For temporarily storing the data, you have some options:
Temporary tables (Use RetainSameConnection = true), so that session context is maintained. From temporary tables, you can load to final table. Temporary tables Retain Same Connection
Recordset destination (It is in-memory object). From the record set destination, you can load to final table in a Dataflow task or in a script task. RecordSet destination in Dataflow task
Raw file destination (It is storing the data in the native format and easily can be reused) Raw file destination
Related
I would like to load incremental data from data lake into on premise SQL, so that i created data flow do the necessary data transformation and cleaning the data.
after that i copied all the final data sink to staging data lake to stored CSV format.
I am facing two kind of issues here.
when ever i am trigger / debug to loading my dataset(data flow full activity ), the first time data loaded in CSV, if I load second time similar pipeline, the target data lake, the CSV file loaded empty data, which means, the column header loaded but i could not see the any value inside file.
coming to copy activity, which is connected to on premise SQL server, i am trying to load the data but if we trigger this pipeline again and again, the duplicate data loaded, i want to load only incremental or if updated data comes from data lake CSV file. how do we handle this.
Kindly suggest.
When we want to incrementally load our data to a database table, we need to use the Upsert option in copy data tool.
Upsert helps you to incrementally load the source data based on a key column (or columns). If the key column is already present in target table, it will update the rest of the column values, else it will insert the new key column with other values.
Look at following demonstration to understand how upsert works. I used azure SQL database as an example.
My initial table data:
create table player(id int, gname varchar(20), team varchar(10))
My source csv data (data I want to incrementally load):
I have taken an id which already exists in target table (id=1) and another which is new (id=4).
My copy data sink configuration:
Create/select dataset for the target table. Check the Upsert option as your write behavior and select a key column based on which upsert should happen.
Table after upsert using Copy data:
Now, after the upsert using copy data, the id=1 row should be updated and id=4 row should be inserted. The following is the final output achieved which is inline with expected output.
You can use the primary key in your target table (which is also present in your source csv) as the key column in Copy data sink configuration. Any other configuration (like source filter by last modified configuration) should not effect the process.
I'm trying to create a SSIS package which will copy data from Table-A on Server-A into Table-B on Server-B. And to avoid duplicates, I want to update the data of the records which already exist in Table-B if there are any changes to the data. Please let me know what would be the best approach for this.
Thank You
You should use the SSIS Sort Transformation to remove duplicate records
Drag Sort Transformation and Connect Flat File Source to it. Double-Click on Sort Transformation and Choose the columns to sort. Also Check the Checkbox : Remove rows with duplicate sort values and then click OK
The SSIS Sort Transformation task is useful when you need to sort data into a certain sort order.
Create regular data flow with 2 components - OLE DB Source and OLE DB Destination (I assume you are using MS SQL Server, in general, use whatever components your company uses to connect to the DB).
In case of 2 DBs, create 2 connection managers, each pointing to its DB. Point OLE DB Source to first connection manager configured to point to source of data, and OLE DB Destination to second connection manager configured to point to destination DB.
Now point OLE DB Source to the source table in source DB, leave all the fields intact. Connect source and destination components with green arrow originally going out of source component. Now point OLE DB Destination to the destination table in target DB. Double-click destination, go to mappings and make sure they are correct (SSIS tries to map automatically using strick name matching), otherwise (in case names are different) connect source and destination fields manually. That's it, you just don't provide mappings for the fields which cannot be accommodated by destination table.
Alternatively, you can leave out the columns you don't need at source component - double-click it, go to Columns and uncheck columns you don't need.
Overview
I have a Data Factory copy activity in a pipeline that moves tabular data (.csv) from a file in Azure Data Lake into a SQL database-landing schema.
The table definitions will be refreshed each load, in principle, and so there should not be errors. However, I want to log errors in the case that the table exists and the file cannot be mapped to the destination.
I anticipate the activity failing when it cannot match the column to the destination table definition. Strangely my process succeeds despite not loading the file into the database.
Testing
I added a column in my source file.
I did not update the destination database table definition.
I truncated the destination table.
I unset fault tolerance.
Deleted all copy activity logs (nascent development environment, so this is OK).
Run the pipeline.
Check Data Factory pipeline Output, 100% success rating!?
Query destination table (empty).
Open each log file and look for relevant information (nothing just headers per copy activity call).
Copy activity settings
SQL Server 2012: using a SSIS package, how to validate the source records for duplicate before inserting?
Our source file is a .csv. We are facing duplicate records loaded in the staging table.
At present , we are following manual process of loading data.
How to validate the source file data against the destination table before loading and load only the valid records? Possibility of loading duplicate records not only because of the source file having duplicate records in it but also reloading the same file to the staging table.
We are not Truncate the staging table. We are keeping records as is.
Second question : How to pick the name of the source file and pass it in the loading ? Possibly having a derived column as "FileName" which will get loaded along with raw data to the staging table.
The typical load pattern I use in this case is:
Prepare a staging table that matches the source file
In SSIS run a SQL Task with TRUNCATE StagingTable; (which clears it out)
Then, run a data flow task that loads the entire data file into the staging table
Lastly, merge the staging table into the final table.
I prefer to do this last step in a SQL Task also:
INSERT INTO FinalTable
(PrimaryKey,Column1,Column2,Column3)
SELECT
PrimaryKey,Column1,Column2,Column3
FROM StagingTable SRC
WHERE NOT EXISTS (
SELECT * FROM FinalTable TGT WHERE TGT.PrimaryKey=SRC.PrimaryKey
);
If you prefer a graphical UI, and you don't mind the extra network traffic, and slower processing time, you can do the same type of merge operation using lookups. You can even use the SCD component but I strongly discourage it's use.
Whether you do it in T-SQL or the UI, you need a key that can be used to uniquely identify the records (referred to as PrimaryKey in my example). If you don't have this key, there is no way to 'deduplicate'
Note in this example you have a 'real' staging table whose only purpose is to get the data file into the database. Then you have a final table that contains the final consistent result
Also note that this pattern only adds new rows - it will not update existing rows if they change in the data file.
Given your exact scenario (of loading the same file again), I would first check if the data is even loaded to the staging table. If you do that, you don't have to worry about checking the duplicates at record level.
How are you setting the connection to the file? Most of the data loads I have dealt with, I designed for-each-loop-container where the file name/path would be populated in a user variable. As you said, you could just use a derived column transform to add a new column which gets the value from a variable. If you don't have the file name in a user variable, you could use expression task in the control flow to populate it.
To cover your exact requirement, I would use the above step to populate the file name in the table. You could even normalize to a different table instead of storing long file name for every data record. Once you have all the file names in the database, you could just have an "Execute SQL" at the beginning to see if that file name is already in the database.
Two years back I have faced the same problem with importing TSV files.
I tried many other solutions but best I could design is C# code script for such validation at its best.
What I did as a solution
Create one C# DataTable object in memory with Primary Key constraints,
like:-
DataColumn[] keyColumn = new DataColumn[30];
keyColumn[intJ] = dtFilterdPK.Columns["Column name"];
Then try to add one by one row from your CSV to this DataTables.
Whenever your data will get Duplication based on Primary Key will have an error
Handle this error code in (TRY)..CATCH block and make this duplication error as per your logging requirement.
Avoid those error records importing in DataTable object.
Atlast import your CSV file into your table as BulkImport
Like:
using (SqlBulkCopy bulkCopy = new SqlBulkCopy(myConnection))
{
bulkCopy.DestinationTableName = "Your DB Table Name"; //Assign table name
bulkCopy.WriteToServer(dtToBeImport); //Write into Actual table.
}
Hope this will help you.
I am just trying to find out whether this is the right way to do this task.
Any other suggestions to improve this is greatly appreciated.
I have the following on my SSIS package.
Data Flow task and established a OLE DB connection to the source database where the view is.
Execute SQL task - I am executing a query with a INSERT INTO Destination Except (all those records that are already there from the source.)
Send mail task is to send out an email.
How to know that the data transfer is successful? So that I can use the send mail to
indicate success or failure.
How to schedule this package so that it runs automatically (Every Tuesday.)
I have tried the suggestion below. Please refer to the new Data Flow task.
OLE DB Source - Points to a view in database server 1
Lookup gets all the rows from OLE DB source. (the rowcount on source and on the lookup)
matches.
On the lookup task, I have configured error output to use 'Redirect row' on all the mapped columns.
On the OLE DB Destination (Destination table where it already has a subset of records from the source. So the Configured Error output to get unmatches rows for insert.
When, I execute the package - I am getting an Primary key constraint error as - Cannot insert duplicate key.
Any suggestions?
You will want to double click the connector from the Execute SQL Task to Send Mail Task Currently it's green which indicates it will only take that path on Success. You will want to update the constraint to be on Completion as you don't care if it's Success or Fail.
It sounds like you have your data flow pulling all of the data from your source and writing to a staging table. In your Execute SQL Task, you then use a query to add data into your target table where it doesn't exist.
This can be consolidated into a single Data Flow. Between your OLE DB Source and OLE DB Destination, add a Lookup task. Since you are on 2005, the Lookup behaves a bit differently than 2008+. You will write a query that pulls back the business keys in your target table and then compares that to what is coming from your OLE DB Source. Map those keys in the interface.
You only want the rows that aren't matched so you will need to get the "unmatched records" from the lookup. In 2005, the option for Unmatched output didn't exist so you will need to route the Error output to your OLE DB Destination.
Andy Leonard has a nice little writeup on how to accomplish this: Configuration an SSIS 2005 Lookup Transformation for a Left Outer Join The only difference for your case, is that you don't care about the matched rows. Instead of Ignore Failure, you want to select Redirect Row. Then when you go to connect the Lookup to the OLE DB Destination, you will be presented with two options. The Green Connector is the Matched, Red Connector is the Unmatched rows. Tie the Red path to your Destination